There is a remote conference system in which images and sounds acquired by communication terminals, which images and sounds can be input to or output from, are transmitted or received among the communication terminals via a network and a conference server, whereby a remote conference is performed. For example, there is a remote conference system capable of saving transmitted or received media data at the time of a remote conference. Images and sounds included in the saved media data can be replay later, whereby the contents of the remote conference can be reproduced.
As a known technology capable of saving media data related to a remote conference, there is a remote conference system configured by connecting a plurality of conference terminals to a conference server having a conference data storage unit, via a network. For example, if conference data including images and sounds indicating the situation of a conference is received from the conference terminals, the conference server saves the conference data in the conference data storage unit in real time. Therefore, according to the known technology, it is possible to reproduce and grasp the contents of a remote conference by replay conference data saved in the data storage unit.
Also, in a known remote conference system as described above, media data including images and sounds indicating the situation of a remote conference are transmitted or received in real time among conference terminals participating in the conference, whereby the remote conference proceeds. For this reason, if a delay occurs in transmission or reception of the media data due to congestion in a network among the conference terminals, the delay interferes with the progress of the remote conference. With respect to this congestion in a network, there is a technology in which a transmission side terminal intentionally discards packets configuring a portion of media data in a case where congestion occurs in a network. According to this technology, even in a case where congestion occurs in a network, a real-time property is maintained with respect to transmission and reception of media data.